5. Sign Reggie Bush (or Another Pass-Catching Speed Back)

Reggie Bush never became the feature back he was expected to be when he was drafted second overall in 2006 (and it was even a surprise he fell that far).

That's because he became exactly the kind of running back the Detroit Lions need in their backfield right now. And he's coming off the best seasons of his career in Miami.

Initially, I would have shrugged off mentions of Bush, as I'm not a big believer in spending on big-name free agents, but then this happened. Now, I love Nate Burleson, and he's one of the Lions' few locker-room leaders. But he's not exactly a numbers guy in the front office. But I have to listen when he and Matthew Stafford both lobby for signing Bush.

Burleson and Stafford are the two players most likely to be asked to lower their salary-cap numbers this year. So their endorsement of Bush might mean Burleson is willing to take a pay cut and Stafford is willing to renegotiate the terms of his contract.

So this could be a great fit for Detroit. Bush is coming off a couple of great seasons, and at age 28 (in March), he'll be looking for his last big cash-in. If the Lions can work it out, that's great.

Without that, I'm just not sure the Lions have the payroll to give Bush as much as he made at USC.

4. Find a Starter (or at Least Insurance) at Right Guard

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This is Bill Nagy the last time he was in a Dallas Cowboys uniform. He was a starter at center for four games in his rookie season, then fractured his ankle.

A high ankle sprain early in the 2012 preseason led to his eventual release from the Cowboys and his acquisition by the Lions. If healthy, he could be a reliable starter for the Lions at any interior line position.

That's if healthy, and he could be. Yeah, Nagy was starting for the Cowboys, but the fact that they were starting a seventh-round rookie at center doesn't speak too well of the overall composition of that line, does it?

Much about Nagy is unknown. He has that magic word "potential" and seemed competent with the Cowboys. But that's an extremely small sample size combined with a lot of injury concerns. Teams don't start potential. They start talent, and we really don't know how much of that Nagy has just yet.

So the Lions need to make it a priority (albeit a relatively low one) to find someone to play right guard in the event that Nagy is either not good enough or not healthy enough to fill the role.

3. Retain the Starting Linebacker(s)

DeAndre Levy and Justin Durant are headed for free agency. Both are effective (though not flashy) starting outside linebackers in a 4-3 scheme.

Both fit well in Detroit, but both may not return.

The Lions have shown interest in retaining their starting linebackers, but if another team takes a shine to one of them, it's hard to say whether the Lions will be interested in winning a bidding war.

That said, there isn't enough talent (not enough that's ready, anyway) on the team for the Lions to lose both Durant and Levy. They need to at least re-sign one of them. I'm just torn on which.

Durant has expressed a desire to stay, but the Lions will have an interest in making Levy stick since he is one of the current management's first draft picks. In terms of age and ability, they're basically a wash. Durant is a little more productive, but also a little older. There's a good chance he'll also be a little more expensive.

It's good that the Lions have Steven Tulloch to anchor the middle for years to come. But with as much upheaval as there is likely to be on the defense this offseason, a little more stability couldn't hurt.

2. Keep Louis Delmas (for a Reasonable Price)

Louis Delmas does it all. He can run, hit, cover and catch, and he plays with tremendous fire. His instincts are solid (though he often overpursues), and he's a vocal locker-room leader.

Problem is, he spends too little time in the locker room and too much time in the operating room. Less time on the field, more time on the trainer's table.

That said, the Lions don't have any better options at safety, and his injury history should keep teams from overpaying to bring him in, potential aside.

Meanwhile, the Lions need only look to Matthew Stafford to see why re-signing Delmas is a good idea. Stafford took on the "injury-prone" label his first couple of years, then played 32 consecutive games and broke a bunch of team records in the process.

Now, Delmas's injury issues have lingered for longer, and they all seem to center around his knees (whereas Stafford kept getting injured in different places), so it's far more likely that his issues are a real long-term issue.

But if the Lions can get him for about two years at a bargain price, they can have enough time to make a final decision on his future (and perhaps have a more stable cap situation to re-sign him long term, should they want to).

Honorable Mentions (and Some Givens)

There are a number of players who the Lions should retain (or try to, at least), but they didn't fit into the "high priority" category for one reason or another.

Let's address some of those here.

All Restricted or Exclusive-Rights Free Agents

The Lions have a bunch of talented players who are RFAs or ERFAs, and they will want to keep them. Guys like Joique Bell, Willie Young, Ricardo Silva, Amari Spievey and Jason Fox fall into this category.

But they don't count as a high priority, because the Lions don't have to prioritize them. They basically just sign them for a set amount, and that's it. It's more a procedure than a priority.

Cliff Avril

The Lions will absolutely make a bid to keep their top pass-rusher under contract, and understandably so. They have no natural DEs under contract, and Avril has been a big part of the defense.

But Avril doesn't get the "priority" tag because it seems increasingly likely that he'll be priced out of the Lions' range. The Lions won't use the franchise tag on him again this year. So it seems like everyone is somewhat resigned to letting him walk.

The Lions would love to keep Avril under contract, but they've clearly not been as adamant about it as they were last year.

Greg Jennings and Other Superstar-Caliber Players

OK, yes. It would be awesome to get Calvin Johnson and Greg Jennings in the same offense.

It would not, however, be awesome to put a quarter of the salary cap into the wide receiver position.

It was enough of a stretch to put Reggie Bush on this list, but I did it because Nate Burleson and Matthew Stafford are apparently lobbying for it, which would seem to indicate that the front office has at least some interest. It doesn't change the fact that the Lions have less than $2 million under the salary cap to spend, and the draft hasn't happened yet.

So while guys like Jennings, Jarius Byrd and Andy Levitre would probably be great players in Detroit, the salary cap is there for a reason, and it's going to prevent a lot of those moves from happening, especially this year.

1. Keep Chris Houston

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The Lions are undeniably in transition in the secondary. Everything seems unsettled, and it doesn't appear any starting job (or even roster spot) is safe.

But through all the upheaval the Lions have had through the years, Chris Houston has been a lone constant. He has been consistently on the field (he's been injured, but time missed has been minor compared to the rest of the unit), and has improved each year.

Sure, Houston may not be a Pro Bowl cornerback, but the Lions aren't going to get one of those without blowing up the salary cap. Houston is an effective alternative who should come cheaper than the elite tier.

If the Lions lose Houston, they'll have to find a replacement. Nobody on the roster is currently anywhere near his level of play. And it's unlikely that they'll be able to find someone as effective as Houston for the same amount of money, especially given Houston's familiarity with the system.

Without a doubt, keeping Houston in the fold is the top priority for the Lions this offseason, for the sake of their secondary and the salary cap.